tree 0d7c54159ca8e9c4d4e113597d3c7c08d9f98e84
parent 8d99641f6c1af806cd5d9e6badce91910219a161
author Rafael J. Wysocki <rjw@sisk.pl> 1295472434 +0100
committer Linus Torvalds <torvalds@linux-foundation.org> 1295577017 -0800

ACPI: Introduce acpi_os_ioremap()

Commit ca9b600be38c ("ACPI / PM: Make suspend_nvs_save() use
acpi_os_map_memory()") attempted to prevent the code in osl.c and nvs.c
from using different ioremap() variants by making the latter use
acpi_os_map_memory() for mapping the NVS pages.  However, that also
requires acpi_os_unmap_memory() to be used for unmapping them, which
causes synchronize_rcu() to be executed many times in a row
unnecessarily and introduces substantial delays during resume on some
systems.

Instead of using acpi_os_map_memory() for mapping the NVS pages in nvs.c
introduce acpi_os_ioremap() calling ioremap_cache() and make the code in
both osl.c and nvs.c use it.

Reported-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>